In quickbooks online Time how do I create multiple assignments for one customer?

Hi, @mrsnostalgia. I'm here to help.

In QuickBooks Time, if you need to assign multiple tasks or projects to the same customer, you can create sub-customers and name them after the tasks or projects. Here's how you can achieve this: 

1. n QuickBooks Online, go to Time, then Assignments.
2. Or, in QuickBooks Time, go to Jobs or Customers.
3. Select Add sub job + next to the job or customer.
4. Enter the sub-level job or customer name.
5. Select Save to add the next sub-level job or customer.
6. Select Cancel to close the job or customer editor.

After this, let me add this refererence about tracking billable time by job by setting up jobs as sub-customers in QBO: Enter billable time by job in QuickBooks Online.

We're always here in the Community should you need further assistance assigning multiple assignments to the same customer. We'll do our best to assist. Take care.